Experimental Application of DAF Hybrid Process to Remove Algae Particles for Conventional Water Treatment Processes and Change of Particle Characteristics

재래식 정수처리공정에서 조류입자 제거를 위한 DAF Hybrid 공정의 실험적 적용과 입자특성 변화

  • Kwak, Dong-Heui (Faculty of Environmental and Chemical Engineering, Seonam University) ;
  • Yoo, Seung-Joon (Faculty of Environmental and Chemical Engineering, Seonam University)
  • 곽동희 (서남대학교 환경화학공학부) ;
  • 유승준 (서남대학교 환경화학공학부)
  • Received : 2008.02.02
  • Accepted : 2008.02.26
  • Published : 2008.06.30

Abstract

There are many water treatment plants built over couple of decade ago in Korea. For most of those plants, they are required a countermeasure to cope with the deterioration caused from the superannuated facilities and the objective materials change of water treatment from inorganic particles like clay to algae particles due to eutrophication of lake and reservoir. A series of field and laboratory experiments was performed to investigate the feasibility of DAF hybrid process and the variation of particle characteristics by applying the additional DAF unit in conventional water treatment processes. On the basis of this experiments, the DAF was effective as an additive process in filtration basin (DAF-CSF combination processes). Using DAF-CSF combination process, the efficiency of stable particle removal can be achieved to produce the safe drinking water.

우리나라는 상수도시설의 노후화와 그 동안의 상수원 수질변화에 대응한 정수처리공정의 개량과 개선이 요구되어지고 있는 상황에 있어서, 기존의 정수처리공정에 어떠한 시설개량이나 설비의 보완 없이 DAF 공정을 추가하여 점토와 조류입자를 효과적으로 제거할 수 있는 DAF hybrid 공정의 적용성을 살펴보고자 일련의 실험을 실시하였다. DAF 공정의 설치위치는 조류입자의 제거에는 응집지나 침전지 전단을 이용하는 DAF-CGS 공정조합보다는 침전지 후단 또는 여과지 전단을 이용하는 DAF-CSF 방식이 더 효과적인 것으로 나타났다. 또한, DAF-CSF hybrid 공정을 도입함으로써 기존의 상수처리조건과 동일한 처리속도(수리학적 부하량)에서 처리효율이 향상될 것이며, 높은 수리학적 부하에서도 재래식 상수도시설에 적용하여 안정된 처리효율을 얻을 수 있을 것으로 판단되었다.

Keywords

Acknowledgement

Grant : 2004년도 특정기초 연구

Supported by : 한국과학재단

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